Photopolymerization of hybrid organic/inorganic materials based on nanostructured units for photonic applications

In this work we report on the study of the photopolymerization process in hybrid organic-inorganic films containing photopolymerizable acrylic and methacrylic groups and. The films are doped with a proper photo-initiator for radical polymerization of (meth)acrylic units and are prepared using the sol-gel technique. The photo-initiator is activated by using continuum (single-photon polymerization) or pulsed (two-photon polymerization) laser sources at different wavelengths. After the development of the unexposed regions with a suitable solvent, the photopolymerized structures are observed with microscopy techniques. The effects of the composition of the photopolymerizable mixture, the irradiation parameters (laser power and exposure time) and the external atmosphere in which the photopolymerization is performed are investigated. The fabrication of 3D microstructures using multiphoton absorption processes is a promising technique that involves low amount of incident exposure dose with potentially high spatial resolution.

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